I don't buy "specialized survival bags". I have a nice internal frame backpacking backpack I picked up at Costco for 55 bucks when I was in Boy Scouts to replace my inherited 1970's Kelty external frame. I've used it to go on multi-week trailblazing treks and fits all of the gear I would need to just survive, including a fishing pole, pocket rocket camping stove and propane fuel, mixed fuel stove (pain in the ass to use, but necessary at high altitude) and fuel, sleeping pad, tent, mummy bag, spare clothes, water purifying pump, canteens, camelpak, soap, TP, spare comfortable shoes, cookware etc. I can strap a day trip pack to the back of it filled with more useful goodies, along with a shovel (they do actually come in handy more often than you think), rope for lashing, a small hatchet, and although I haven't tried it, I'm sure I could rig up a sheath for a long gun, and also carry a holstered pistol at the same time. On the last Sierra Trek I did I think my pack weighed 75 lbs, which is not exactly light weight nor does it allow you to be very agile.
Going backpacking during a national crisis is not exactly something I'd be too interested in though, but it is a possibility. Nothing I bought was specially designed by any survivalist, although the pocket rocket stove and the backpack were designed for backpackers.
My advice for survival preparedness is to just go buy a Boy Scout manual. Honestly, it's all in there. You don't need to spend tons of money on books from all kinds of survivalist people. A simple Boy Scout manual will give you everything you need to know for basic first aid, camping, backpacking, survival technique, and food foraging.